"I didn't feel trapped in the wrong body, but mismatched - my inner self was somehow mismatched with my outer body," says Kaspar Wan as he happily poses for photos in a park near his home. The sun's out and Wan, who usually goes by his nickname Siu-keung, talks candidly about his life - one that started as a girl.

For years Wan struggled with gender dysphoria, a condition in which someone is uncomfortable with his or her biological gender. He strongly identified with the male psyche, and wanted to be a man.

Growing up, he says, "to make myself comfortable with the 'girl' identity, I would position myself as a 'boyish girl'. But as I got older, the uncomfortable feelings grew stronger. I knew I didn't want to become a woman".

Eventually, in December last year, Wan underwent a subcutaneous mastectomy - a complete upper-body surgery in which most of the breast tissue is removed. "After the surgery I only had a couple of small scars. The surgery is fairly simple."

But, for Wan, that procedure ended years of emotional turmoil.

"It was the best decision I've made. My only regret is not having the surgery earlier," says the 34-year-old freelance video producer. "I spent many years struggling with body issues. I couldn't look at my reflection in the mirror. I was unhappy, stressed and confused and would ask myself whether or not I was a homosexual. I just didn't fit in and the feelings of isolation made me think about suicide.

"As far back as three years old, I have wanted to be a boy. Now I've had the surgery, I can face myself."

Transgender issues have been in the limelight following a groundbreaking decision by the Court of Final Appeal last month that allowed a transsexual woman, "W", to marry her boyfriend, forcing the government to make a U-turn on marriage laws.

The long-held belief in Hong Kong was that transgenders were 'unnatural' or 'freaks'

Kaspar Wan

"W", who had government-funded sex realignment surgery (SRS) more than five years ago, sought to marry in Hong Kong but was refused as her birth certificate still classed her as male. The government had argued the union would constitute a same-sex marriage, which is illegal in Hong Kong.

Wan says the case was not only a victory for "W" but for human rights in Hong Kong.

"The long-held belief in Hong Kong was that transgenders were 'unnatural' or 'freaks' … In the past, Hong Kong society was tense about laws protecting gender identity, but after the 'W' case it seems people want to learn more about transgender issues.

"There was a lot of ignorance in Hong Kong. People only associated transgenders with ladyboys in Thailand - that was the only connection. I was lucky to have support from my friends and family," says Wan, who lives with his parents and has one brother and a sister. "There's still a long way to go, but the 'W' case has helped."

The first sex realignment surgery in Hong Kong was performed at the Princess Margaret Hospital back in 1981. According to the Hospital Authority, the number of surgeries has risen in the past five years (see table) and most are performed in Ruttonjee and Tang Shiu Kin hospitals.

To qualify for sex realignment surgery, a patient must undergo two years of personality evaluation, surgical assessment and hormone treatment. The waiting period gives candidates an opportunity to fully consider their decision, as the operation is irreversible.

Cynthia Ho, a sex therapist at Neo Health consultancy in Central, says the first step when assessing a candidate for sex realignment surgery is to rule out any genetic or hormonal disorder. "One would also have to have a strong dislike of their gender, to feel distressed about it, and show a strong desire to be living as the opposite sex."

Candidates also need to be assessed psychologically for mental and mood disorder, gender identity issues and possibility of sexual abuse, she says. "We would have to dig into the actual reason why one wants to change his/her gender, and determine if this change would provide a better quality of life."

"Candidates usually have to live as the opposite sex for at least two years before sex reassignment is performed. During this time their psychological progress is closely monitored. Candidates must also meet with an endocrinologist to have hormone manipulation to induce physical changes."

For many people who undergo sex realignment surgery, the waiting period is the hardest part.

"The process for me started 2½ years ago with a visit to the Prince of Wales Hospital," Wan recalls. "I saw a psychiatric doctor and told him my story. I was referred to other doctors, including psychologists and an occupational therapist. I've been taking hormones since the end of 2011 and will take them every three weeks for the rest of my life."

The shots of male hormones helps "masculinise" the chest by adding hair and muscle mass. "Hormone therapy is just like going through puberty again, but this time as a boy, so my voice was lowered, I became more hairy, and found it easier to build muscles ...

"I call myself a transman. I've finished with surgery - that's it for me. I didn't have the full surgery because it's quite complicated and high risk. I will continue to see doctors with regular follow ups but, obviously, they won't be as intense as before the surgery."

Wan says the intense pre-op consultation is essential. "It's vital people have a psychological assessment. They may not know their bodies well enough."

Dr Sam Winter, an associate professor at the University of Hong Kong and a member of the board of directors of the World Professional Association for Transgender Health, has been working in rights and health for transgender people for more than 13 years.

As he sees it, hormones and gender affirmation surgeries are not only life changing, but can be life saving - "suicide attempts [are] alarmingly high within the transgender community".

Although hormones and surgery go a long way to reduce stress and discomfort, Winter says a major concern is how transgender people are acknowledged within society.

"This is not about surgery and hormones. It's about gender recognition - ID cards and birth certificates, and so on. In this area, the Hong Kong government does little to help transgender people."

Winter says while the ruling on "W" gives those undergoing the fullest possible surgery the right to marry, there are many transgender people for whom these operations are not medically necessary.

"Their mental health and well-being does not depend on undergoing surgery. There may even be medical reasons why they should not undergo it. As a mental health specialist and specialist in transgender health, I have grave misgivings about the current government policy.

"To require sex reassignment surgery as a precondition for transexuals to get a new ID card is cruel, degrading and inhuman … it's coercive medicine."

Winter also supports a proposal to the World Health Organisation to declassify the trans diagnosis as a mental health condition, and instead classify it as a general health condition.

Transpeople have for years argued that they should not be classified as mentally disordered, he says, adding that that the World Health Assembly, the governing body of WHO, is likely to approve these and other recommended changes to International Classification of Diseases in 2015.

If passed, Winter says, it will be as historically important for transpeople as the removal of homosexuality from the WHO list of mental disorders in 1990.

Support for those considering surgery is vital, says Dr Ho Pui-tat, of the Hong Kong College of Psychiatrists. "Patients with gender identity disorder are prone to depression, substance abuse or self prescription of hormones, suicide attempts, and family disruptions, which will need treatment on their own."

Part of the problem is that most people misunderstand transsexuals, Cynthia Ho adds. Because of this ignorance, they experience various levels of social pressure: harassment, discrimination, abuse and even abandonment by their families.

But transgenders don't have a choice, and some can have feelings of being born the wrong sex at an early age, "as early as three or four years old", she says.

"It's not an option. One does not choose to like or dislike their own gender."

As with any other medical procedure, Ho says, after care is important in case of medical complications and to help people "better fit into their new bodies".

For Wan, the gender transition period has, so far, been a smooth one. "I've been very lucky. People are surprised when I tell them but I'm quite outspoken about the subject."

But many transgenders are subjected to prejudice, which is why Wan devotes much of his energy to helping at the Transgender Resource Centre.

"I was very lucky to get support from my family and friends, but this is not the case for all transgenders, so I hope my advice can help them.

"The most important thing to remember is that whoever we are - female or male - we are all human beings, so both should strive to be good people, regardless of gender."